MicroRNA Biosensing through Spectral Interferometry based Surface Plasmon Resonance using Telecommunication Wavelength

The polarisation maintaining (PM) fibre constructed the spectral interferometry-based surface plasmon resonance to detect the very small molecule micro ribonucleic acid (miRNA) with a big biological impact on cancer diagnosis. Other than the linear polariser and birefringence crystal in the input of the traditional spectral interferometry, the polarisation controller was simply placed on the injected light to control the transverse electric and transverse magnetic polarised magnitudes through the stable polarisation state of PM fibres for distinct dynamic-range fringes on the optical spectrum analyser (OSA). Owing to the high precision and stability control of operating wavelengths in optical fibre communications, the low-coherence telecommunication source was utilised to detect 21-mer deoxyribonucleic acid which changed U to T according the miRNA-21 sequence. The sensitivity with probing was showing 0.065 nm/(μg/ml), which implied the resolution as 0.3 μg/ml under the 0.02 nm wavelength accuracy on OSA.